T4
Solution heat-treated at about 495 °C, quenched and naturally aged at room temperature. High strength with the best toughness and fatigue crack resistance. Quench stresses remain, so large forgings can move during machining.
High-strength copper alloy forgings
2024 Aluminium Forgings
2024 aluminium forgings are open-die and closed-die parts, rolled rings and forged bar in the aluminium-copper-magnesium alloy best known for fatigue resistance and high strength at moderate temperatures. Forging refines the cast structure and aligns the grain flow with the part, so a 2024 forging is tougher and more reliable than the same shape machined from plate. Metline supplies 2024 forgings in T4, T6 and T852, made to drawing and certified, to customers worldwide.
- Alloy
- 2024 (Al-Cu-Mg)
- Tempers
- O, T4, T6, T852
- Forms
- Hand forgings, rings, bar, discs
- Key strength
- Fatigue and damage tolerance
What is a 2024 aluminium forging?
2024 contains about 4.4 % copper and 1.5 % magnesium. After solution treatment, these elements precipitate as fine Al-Cu-Mg particles that give the alloy high strength even in the naturally aged T4 condition, together with excellent resistance to fatigue crack growth.
Forging starts with a cast or extruded billet of 2024 that is heated to roughly 420 – 460 °C and shaped under a press or hammer. The working breaks up the coarse cast structure, closes internal porosity and makes the grains flow along the contour of the part. A forged ring, disc or fitting therefore has better ductility, fatigue life and toughness in the critical directions than the same shape cut from thick plate, where the grain runs only one way.
2024 is not the most common forging alloy; 2014, 2618, 6061 and 7075 are forged in larger volumes. It is chosen when a design was qualified on 2024 (often aircraft parts carried over from plate or bar), when fatigue life is the governing requirement, or when parts must keep strength at temperatures up to about 120 – 150 °C, where 7xxx alloys begin to soften. Most 2024 forgings are open-die hand forgings, rolled rings, forged discs and forged bar, which are then machined to the final shape.
2024 chemical composition (wt %)
Registered Aluminum Association limits, used also for EN AW-2024 in EN 573-3. The certificate for each heat reports the actual analysis.
| Element | Minimum | Maximum | What it does |
|---|---|---|---|
| Copper (Cu) | 3.8 | 4.9 | Main strengthening element; also lowers corrosion resistance |
| Magnesium (Mg) | 1.2 | 1.8 | Combines with copper for strong natural ageing response |
| Manganese (Mn) | 0.30 | 0.9 | Controls grain structure and adds strength |
| Silicon (Si) | — | 0.50 | Impurity |
| Iron (Fe) | — | 0.50 | Impurity; lower Fe and Si improve toughness |
| Chromium (Cr) | — | 0.10 | |
| Zinc (Zn) | — | 0.25 | |
| Titanium (Ti) | — | 0.15 | Grain refiner |
| Others, each / total | — | 0.05 / 0.15 | |
| Aluminium (Al) | Remainder | About 90.7 – 94.7 % |
Mechanical properties of 2024 by temper
The figures below are typical handbook values for wrought 2024 and show how the tempers compare. Forgings reach similar values in the longitudinal (grain-flow) direction; transverse and short-transverse values are lower and depend on the part shape and section. Guaranteed minimums for a forging come from its purchase specification and appear on the certificate.
| Temper | Tensile strength (typical) | Yield strength (typical) | Elongation | Brinell hardness |
|---|---|---|---|---|
| O (annealed) | 186 MPa / 27 ksi | 76 MPa / 11 ksi | 20 % | 47 HB |
| T4 / T351 | 469 MPa / 68 ksi | 324 MPa / 47 ksi | 19 – 20 % | 120 HB |
| T851 / T852 (artificially aged) | About 485 MPa / 70 ksi | About 450 MPa / 65 ksi | 6 % | 128 HB |
T852 is the forging equivalent of T851: solution treated, stress-relieved by 1 – 5 % cold compression, then artificially aged. Values shown for T851 are a guide only.
Physical properties (T4 / T3 family)
- Density
- 2.78 g/cm³ (0.100 lb/in³)
- Modulus of elasticity
- 73.1 GPa (10,600 ksi)
- Fatigue strength (5×10⁸ cycles)
- About 138 MPa (20 ksi)
- Thermal conductivity
- About 120 W/m·K
- Electrical conductivity
- About 30 % IACS
- Melting range
- About 500 – 638 °C
Which temper for a 2024 forging?
T6
Solution treated and artificially aged. Higher yield strength than T4 and better resistance to intergranular corrosion, with lower elongation.
T852
Solution treated, cold-compressed 1 – 5 % to relieve quench stress, then artificially aged. Chosen for hand forgings and rings that will be heavily machined, because parts stay dimensionally stable.
O
Annealed for further forming or as stock for later heat treatment by the customer.
Artificially aged tempers (T6, T852) keep their properties better at elevated temperature and resist stress-corrosion cracking better than T4. Naturally aged T4 is preferred where toughness and fatigue crack growth resistance govern. Heat treatment practice for aerospace forgings is controlled by AMS 2770 or the customer's process specification.
2024 standards and international equivalents
| System | Designation | Notes |
|---|---|---|
| Aluminum Association / UNS | 2024 / A92024 | Composition registered with the Aluminum Association |
| European (EN) | EN AW-2024 / EN AW-AlCu4Mg1 | EN 573-3 composition; EN 586 covers forgings |
| German Werkstoff | 3.1355 | Common on DIN and LN aerospace drawings |
| ISO | AlCu4Mg1 | ISO 209 |
| Japan (JIS) | A2024 | JIS H4140 covers aluminium forgings |
| Chinese grade (similar) | 2A12 | Close but not identical composition; treat as a substitution needing approval |
| Aerospace forging specifications | AMS-QQ-A-367, AMS 2770 (heat treatment) | Confirm that the specification on your drawing covers 2024 in the required form and temper |
Forgings are almost always bought to a drawing plus a material specification. Tell us both, together with test directions, ultrasonic class and any first-article requirement. If a drawing quotes a superseded military specification, we will propose the current equivalent for your approval.
2024 forging forms we supply
Open-die (hand) forgings
Blocks, rectangles and stepped shapes forged between flat dies, ideal for prototypes and low volumes where tooling for closed dies is not justified.
Rolled rings
Seamless rings formed by piercing a forged disc and rolling it on a ring mill; grain runs around the circumference.
Forged discs
Upset pancakes and discs for wheels, flanges and housings, with radial grain flow.
Forged bar
Round, square and rectangular bar forged from large ingots, used where extruded bar is not available in the size or quality needed.
Closed-die forgings
Near-net shapes for repeat production; justified at higher volumes because of die cost.
Machined forgings
Rough- or finish-machined to drawing, with inspection reports.
Typical supply envelope
- Rings
- Outside diameters from about 200 mm up to several metres, depending on wall and height
- Discs
- Diameters from about 100 mm to over 1,000 mm
- Hand forgings and bar
- Section sizes from about 50 mm up to several hundred millimetres
- Condition
- As-forged, rough-turned or machined; heat treated to the ordered temper
Feasible sizes depend on the alloy, shape and specification. Send a drawing and we will confirm what can be made.
Testing and inspection of 2024 forgings
Typical inspection plan
- Chemistry
- Heat analysis of the forging stock
- Tensile tests
- From prolongations or sacrificial forgings, in the directions the specification requires (L, LT, ST)
- Hardness and conductivity
- On every forging or a sample, to confirm heat treatment
- Ultrasonic inspection
- To AMS-STD-2154 or ASTM B594 class AA, A or B as ordered
- Grain flow
- Macro-etch of a sectioned first article for closed-die forgings
- Dimensions
- Full dimensional report against the forging or machining drawing
- Certification
- EN 10204 3.1 certificate; 3.2 with third-party witness on request
Short-transverse properties are where forgings most often disappoint. If a part is loaded through its thickness, tell us at the enquiry stage so the forging can be designed to put grain flow where it is needed and the test plan can include short-transverse specimens.
Machining, joining and protecting 2024 forgings
Machining
Good in T4, T6 and T852 tempers; chips break well and surface finish is good. T852 forgings move least when large volumes are removed.
Joining
Fusion welding is not recommended because of hot cracking and strength loss. Use bolts, rivets or adhesive bonding; friction stir welding is possible with qualified procedures.
Corrosion protection
The high copper content lowers corrosion resistance. Sulphuric or chromic acid anodising, chromate conversion coatings and primers are standard on aircraft parts.
Temperature
Keeps useful strength to about 120 – 150 °C, better than 7075; for higher temperatures 2618 or 2219 are the usual forging alloys.
Where 2024 forgings are used
- Aircraft structures: fittings, brackets, hinge parts and frames carried over from 2024 plate or bar designs
- Rotating parts: rings, flanges and wheels where fatigue life governs
- Defence: missile and munition components, launcher parts
- Transport: high-performance vehicle and rail parts needing strength at moderate temperature
- Fasteners and hardware: forged blanks for bolts and couplings
2024 forgings compared with 2014, 6061 and 7075
| Property | 2024 (T4 / T852) | 2014-T6 | 6061-T6 | 7075-T6 / T73 |
|---|---|---|---|---|
| Strength | High | High | Medium | Very high |
| Fatigue crack resistance | Very good | Good | Good | Fair |
| Elevated temperature (to about 150 °C) | Good | Good | Fair | Poor–fair |
| Corrosion resistance | Low | Low | Very good | Low (T6) – moderate (T73) |
| Forgeability | Fair | Good | Very good | Fair |
| Typical forging use | Fatigue-critical aircraft parts | Aircraft and truck forgings | General engineering, marine | Highly stressed aircraft parts |
2014 is usually the first choice among copper-bearing forging alloys because it forges more easily, and is often accepted where 2024 is shown on older drawings. 7075 gives more strength, 6061 better corrosion resistance and lower cost. See our 2024 vs 7075 comparison for the full picture.
How to order 2024 forgings
- SpecifyDrawing or forging dimensions, alloy and temper (e.g. 2024-T852), material and forging specification, test directions, ultrasonic class and quantity.
- ReviewWe propose the forging route (open die, ring rolling or closed die), machining allowance and inspection plan.
- First articleFor new parts, a first article with dimensional, mechanical and macro-etch results can be supplied for approval.
- DocumentEN 10204 3.1 certificate with chemistry, heat treatment and test results, plus UT and dimensional reports.
- ShipForgings protected against corrosion and packed in wooden cases, shipped EXW, FOB, CIF or DAP.
References and standards
- ASTM B247 – Aluminum and Aluminum-Alloy Die Forgings, Hand Forgings, and Rolled Ring Forgings
- EN 586-1 to -3 – Aluminium and aluminium alloys: forgings
- SAE AMS 2770 – Heat Treatment of Wrought Aluminum Alloy Parts
- The Aluminum Association – International Alloy Designations and Chemical Composition Limits
- ASM Handbook, Vol. 14A – Metalworking: Bulk Forming (forging of aluminium alloys)
2024 aluminium (aluminum) forgings: frequently asked questions
Why choose a 2024 forging instead of machining from 2024 plate?
Forging aligns the grain flow with the part shape and closes internal porosity, which improves fatigue life, ductility and toughness in the directions that matter. It also saves material for thick, round or ring-shaped parts.
What does T852 mean on a 2024 forging?
The forging was solution treated, stress-relieved by cold compression of about 1 – 5 %, then artificially aged. It keeps parts stable during machining, much as T851 does for stretched plate.
Is 2014 an acceptable substitute for 2024 forgings?
Often, because 2014 forges more easily and has similar strength, but the two alloys differ in chemistry, toughness and corrosion behaviour. A substitution needs approval from the design authority.
Can 2024 forgings be welded?
Conventional MIG and TIG welding is not recommended because the alloy is prone to hot cracking and loses strength. Use mechanical fastening or qualified friction stir welding.
What testing is supplied with 2024 forgings?
Chemical analysis, tensile tests in the specified directions, hardness and conductivity, dimensional inspection and, where ordered, ultrasonic testing, all reported on an EN 10204 3.1 certificate.
Do you ship 2024 forgings internationally?
Yes. Metline supplies forgings worldwide from Mumbai, with export packing and full documentation.
Need 2024 forgings?
Send your drawing, temper and specification. We will propose the forging route and inspection plan and quote a delivered price.
